This special mount kit was designed by Weber to isolate DCO-series carburetors from engine heat and vibration. Each kit includes 2 aluminum spacers, 4 sealing O-rings, 4 spring washers, and 4 self-locking nuts (enough to mount one carburetor). Fits Weber 48 DCO/SP, 50 DCO/SP, and 55 DCO/SP. May not fit licensed copies, clones, work-alikes, or knock-offs.